My Pier project for Losmandy G11

[Manav]

Hi everyone!

Setting up my G11 with RC 10" every night is starting to take its toll on my back. So to shorten the process and make life much easier I have been researching like crazy to get the best pier for the limited views I have.

The Altair Skyshed 8" Observatory Pier (https://www.altairastro.com/product.php?productid=16162&cat=303&page=1) is a good design and allows the installer to modify pier levelling and rotation AFTER installation on the base. The price is quite steep but it's a one time investment and I can always move the pier down the track if need be. The design is based on SkyShedPos's own pier (http://www.skyshedpod.com/) which has has similar features.

My question is has anyone purchased the skyshed or Altairastro pier and if so any feedback would be welcome. Furthermore, has anyone made similar custom pier in Sydney or knows any metal works company that could assist me and save money?

Regards
Yugant

[netwolf]

Manav same problem here but I am thinking of a portable pier which i can leave outside. I looked at this ages ago but never had time to follow through on it. Now looking at the EQ6 Pier, but unsure if this could be used with a G11 and what modification it might need. I also have limited views and need to move about so a perm pier is not in the near future.

[wasyoungonce]

Hi Yugant

I had the same things, just too much load to bring in/out. I contacted Altair on the same thing, they never replied. In practice sending something weighing ~80~10kg from UK is not ideal cost wise.

I had a local workshop make mine. I did up some drawings with CAD (I can send them to you, solid edge 2D drafting, although I can save as other formats) and had them cost & build, allowing them lots of latitude on parts (although I asked for a max dia pipe) and materials.

End product is great, although over budget by 30%...total cost $980 delivered. But it's a beast, ~ 200kg, way over designed but as solid as they come. Absolutely no ringing. I suspect you can change my design downsize materials and still be well within the deflection specs allowable (> .5 arc sec deflection (caculated) (http://www.cloudynights.com/item.php?item_id=1275), lateral force ~22 newtons).

Bert spoke some good info on piers recently, see here (http://www.iceinspace.com.au/forum/showthread.php?t=111597).

Just need to now put in the concrete bas and build a shed around it.:shrug:

[I.C.D]

G'Day Yugant,
My pier is 250 mm x 250 mm x 12 mm as a base I use a 100 mm thick wall pipe about 800 to 900 mm high depending how tall you are on top I used 2 x 200 mm x 200 mm x 12 mm one is welded to the pipe the other is bolted to give you fine adjustment on your height on top of that I used pier adapter plate to mount the EQ6 to the top pier plate .
The base holes are 12 mm bolted the concert pad .The top plate welded to the pier and have 10 mm clearance holes the top pier plate has been tapped to 10 mm and I used thread bar to bolt the top plates together by tapping the top plate when you screw the bolts in they will be flush with the top plate.
You can get all of the above from Metaland or Onesteel or you do a drawing and take it to a metal fabrication place and they can do the lot it will be lot cheaper then buying one from overseas
Ian C :thumbsup:

[Manav]

Brendan - Can I get your CAD drawings :) And where did you get the pier to mount adaptor from?

Does anyone know metal fabrication places in Sydney who may be able to build a pier from a plan for a reasonable fee?

Ian and Fahim - Thanks for the info gents!

[I.C.D]

G'Day Yugant,
I tried all around and got one from altair for a EQ6 it cost me about $190 all up .I tried a couple of engineering company and it was going to cost about $400 to $500 as it is a one off .
If you find someone in Oz who will do it good luck

Ian C:thumbsup:

[wasyoungonce]

Hi Yugant

CAD drawings sent. If you want different format or drawings just holler. I included an excel spreadsheet on pipe deflection calculations...just punch in the pipe dia, wall thickness and length and it calculates deflection.

I just went around local fab houses/welding shops/general engineering houses, small ones are probably better. The most difficult thing to source is large diameter pipe and this costs, have a look on the net, scary! These places have contacts and sourced a 2nd hand pier pipe which reduced my costs. I just specified a minimum dia I would accept. They did the rest and got it powder coated and delivered to me.

Powder coating can add cost up to ~$200 ....depends. Again these places have contacts and can get cheaper than walking in from the street.

I made my pier so I fit another top alloy plate and on this fits the Losmandy MA adapter. I can rotate the MA adapter (it has a centre hole for a bolt so it can rotate and many other holes for bolting) for polar alignment. I can thus drill into the plate and tap other holes to lock down the MA adapter if needed. I got my MA from OS but Bintel sell them.

edit:
I should have said...the pier can be a square cross-section as well. Welding shops usually have 225mm RHS and can mig weld 2 together to form a square pier! This would be cheaper than a pipe!

[el_draco]

There is a really good thread on IIS about pier design. One of the issues with a lot of manufactured piers is the rat cage that seems to be on top of most. Not so good for a range of reasons but especially flexure. For $750 you could get something built that meets your specific needs.

[strongmanmike]

Wow, now THAT'S a pier :eyepop: :thumbsup:

Mike

[White Rabbit]

My G11 has been outside since I got it. Check out the scope and tripod covers from telegizmos 365 range.
I leave everything out there hooked up, cameras, scopes, the lot. Haven't had a single issue.
You'll need the tripod cover as well as a scope cover. My tripod cover never comes off and I leave all my power supplies underneath. They have been bone dry for about the last 8 months. Couldn't be happier with them.

http://www.telegizmos.com/365%20sizes%20and%20prices%20page%2 02.htm

Cheers

[Manav]

After looking at multiple designs I'm thinking of getting the pier plates for G11 from here: http://www.pierplates.com/products_8600.html

All I need is someone help in giving me an drawing to substitute the concrete part with steel with the 3 screws to match the plate design above and I'm ready to go.

Brendan - I've sent you a PM

[wasyoungonce]

Hi Yugant...no PM seen?

As for top plates, yes pier plates do make nice stuff but they are mainly intended for concrete piers, thus have the colloquial "rats cage" for alt/Az adjustment (thought theirs is nicely made and designed). Even if you have a concrete pier all you need, for the G11, is a round top plate and on top of this a Losmandy MA adaptor that bolts to the plate (can probably even do without top plate).

The MA adapter can thus be rotated for Az for rough adjustment then use micro Az adjusters as required. As for Alt, well as long as you pier top is ~+/-15 degrees or so it doesn't matter as thus can be adjusted out by the mounts latitude or Alt micro adjuster.

Absolutely no need for a set of adjustable pier plates in this situation. Thus my pier has none, just bolt MA adapter on top rotate to suit!

edit:
ahh just got an email.
In reply, pretty much what I said above. If you do a concrete pier just use a top plate of any old metal (bolted to the pier) and on this mount an MA adapter so it bolts thru it's centre to this top plate. No need for precision in Alt/Az for above reasons. Rotate the MA to find SCP then drill/tap some more bolts to hold the MA secure although it's centre bolt should be enough.

[Manav]

Draft design check before I start using CAD:

1. Base Plate - 400mm x 400mm x 12mm (Length x Width x Height). The base plate has four concrete anchor bolts 5/8-11 x 12".

2. Tube - 1000mm high with outside diameter 225mm with 9.3mm thickness.

3. Bottom Gussets (four in total) - 750mm high and 150mm from base with 8mm thickness.

4. Top Plate (Pier) - 275mm x 275mm x 12mm (Length x Width x Height). The top plate has four M16 Bolts holes on each side

5. Top Plate (Mount) - 275mm x 275mm x 12mm (Length x Width x Height). The top plate has four M16 Bolt holes on each side as well as holes to fit retrofit the losmandy MA.

[wasyoungonce]

Hi Yugant

Those parts sound fine...except all this depends upon what you local fab house has in stock. If they have to order..then it costs more.

Allow the fab house some latitude on materials but give them a minimum allowable spec you will accept.

[brian nordstrom]

:) I am a boilermaker by trade and have worked in a lot of w/shops here and in NZ , most large w/shops have a lot of scrap pipe an piles of old flanges , of many different sizes just lying around .

Manav's list is a good one his tube is 200mm diameter schedual 80 carbon steel pipe , 150mm sch pipe is 168mm o/d and 100mm sch pipe is 114mm o/d , there are hundreds of off cuts out there if you ask , don't buy new .

A large 12 inch , 150 lb blind flange would make a perfect base about 450 in dia. and its already drilled so that saves labour/costs .
Shop around you might be surprised as over the years I have seen lots of us astronomers given old steel like this for free when the owner/boss discovers its for a telescope .
Brian.

[Manav]

After a frantic start to the year I have finally decided to move the design phase along before the 2014 winter kicks in. I got some measurements done using a ruler. Can someone please confirm that the top plate adaptor which will hold the Losmandy G11 mount has the following specifications:

1. Outside diameter 152.55mm
2. Thickness 6.08mm
3. Calculated inside diameter 140.39mm

I've also decided to change the design a bit to use a square pier instead of a circular pipe. Will have some design pictures up soon.

[Manav]

For the sake of keeping my sanity here is my final design. I intend on purchasing a Losmandy MA adaptor to attach on the top plate and rotating it to get perfect south pole alignment.

Any feedback would be greatly appreciated before I start calling local metal works around the area.

[wasyoungonce]

Yep that's the ticket. Square sectioned or angle iron welded together to form Sq section is a good and more likely cheaper option than hunting for large dia pipe.

Ensure you talk to you fab houses and get written estimates and allow them some variations in materials for things like gussets.

I'd try to make the top plate round if you can (although mine isn't) as this allows better ota positioning overhead. Backfilling is probably unnecessary, I had this same hole for mine but found extra dampening is not required.

Also consider bottom plate mount holes bolt at either side close to the gussets as this is the place where the gussets place tension/compression thru the base.

:thumbsup:

[Manav]

Thanks Brendan and Brian for your feedback!

Next step is to contact the local Fab houses around western Sydney! If anyone has any recommendations I'm all ears!

[wasyoungonce]

I know it won't help Yugant and a little thread hijacking....I was at Stokes appliance parts Palmerston road Ringwood (Melbourne, just off Heatherdale road) and went past CMA Metal recyclers (same location).

I spied with my keen eye a larger selection of used round tube stock of various big diameters; thicknesses and lengths...perfect for a pier project! Also saw some rollers from conveyor belt systems which may suit as well.

FWIW...thread hijack off.....;)

[Manav]

:(

Got a few quotes mostly mentioning I need to downscale to 200 SHS with 5mm thickness for main pipe. Quotes around ~700 bucks

I'll do a re-design and see if I can get further reduction elsewhere.

[wasyoungonce]

Probably about right maybe give the fab house latitude in using used stock, aka if they have used plate or tube.

This can lower costs. I found new tube (I know your not using tube) costs very high but used can be had for 1/3 the price.

[Manav]

So here are the changes:

1. For main body 200 x 5mm SHS at 1100 mm high (Can be any height more than 900mm and less than 1200).

2. Bottom plate reduced to 350mm x 350mm or any stock length around that size with 4 x M20 bolt holes on each side.

3. Top Plate 250mm x 250mm with 4 x M12 bolt holes and a 50mm hole in middle so I can add sand to tube body dampen vibrations if need be.

4. Adaptor plate 250mm x 250mm with with 4 x M12 bolt holes and a 12.7mm diameter hole in middle for mount adaptor

5. Top Gussets that don't require full welding across the length. Since the we are using a smaller diameter for main pipe, the gussets will assist in gaining back some stiffness.

6. Bottom Gussets that don't require full welding across the length. Since the we are using a smaller diameter for main pipe, the gussets will assist in gaining back some stiffness.

[Manav]

So the pier is finally completed thanks to the Frontline Fabrication Team (http://frontlinefabrications.com.au/). The quote I received was reasonable compared to the numerous metal fabrication places I contacted. To makes things easier they even galvanised and sanded it down.

Next step is to start the installation process as follows:

1. 800mm x 800mm x 800mm hole for the concrete slab with M20 L bolts.
2. Apply top soil around set concrete to keep a low profile.
3. Install a slightly raised 1000mm x 1000mm wooden decking around the pier.

Any suggestions? I'm all ears :D

[Octane]

How much did that set you back? :)

H

[Manav]

The pier is 650 add another 150 odd for Galva and sanding.

[Manav]

Update 14/6/14

So the 750mm x 750mm x 650mm hole is now full of concrete and four M20 bolts held together by baseplate template. I used rebar from Bunnings to make sure tensile strength is enhanced.

Next I'm using spray paint for the Pier going for a military green look with a nice Red Soviet Star! :eyepop:

I also ended up purchasing the 365 Series Cover System from Telegizmos (http://www.telegizmos.com/).

Whats Next?

I'm hoping to get the 1.5m decking done around the pier so it looks pretty and can serve as a platform for the permanent cover (which I haven't decided yet)

I have two options:

1. Motel O'Scope kind of fixture with my own custom design. Click Here (http://www.pierplates.com/motel.html)

2. Something similar to a TARDIS; looks good and I can store extra equipment. Click Here (http://www.duncankitchin.org/?blog=show&articleid=13)

Anyway let me know what you think.

[Manav]

Update 22/6/14

The 1.5m decking is well under-way with the foundation framework now bolted together. I went to Masters Home Improvement and got treated timber for the noggins and base.

Dug four additional holes using the post digger and filled it with spare concrete left over from the pier base to ensure the decking stays put.

All I need to do now is put the pier in place and complete the top deck.

Would like to thank my friend for all his help its been a intense project so far.

[Manav]

Update 25/6/14

Almost there with the decking.

Added the weed mat and power point for the observatory. Started putting the decking on top only to realise I was short by 2 pieces.

Hoping to wrap this up on the weekend and get the decking oil and pier paint done as well.

[AstroJason]

Wow mate, its really starting to come along now. Well done! I'll have to come around and check it out soon.

[Poita]

Definitely go the TARDIS.

[Manav]

Looks like that's the easiest option at this stage Peter! It may take a while though :)

[Manav]

Final Update: 19/10/14

Sorry for resurrecting this thread; I just wanted to thank everyone for their advice. My observatory is all done :D

Couple of things I added to the motel-o-scope design:

1. The temperature delta inside vs outside foam insulation is approx. 4°C.
2. The telegizmos cover provides rain protection and adds an extra layer of insulation on top of foam.
3. I intend on adding small de-humidifier and a small AC fan that keeps the air rotating.
4. The design is low key and doesn't stand out like an odd shape in the backyard.
5. Mount is locked on to the pier for security reasons and my optical tube stays indoors mostly.

When required the top cover can be removed for quick access to astrophotography. All electrical points are installed (underground) and have automatic timers.

The whole setup can be moved/uninstalled (excluding the decking) in case I decide to move.

I'd like to once again thank everyone who PM'ed me and gave me much needed advice.

Ciao

[lazjen]

Yugant, how's the pier working out for you? I'm in the process of trying to design/build one for myself now and I'm thinking of using a similar design.

Did you end up filling in the centre of the pier with sand? Is there anything you'd change about it in retrospect?

[oilydog]

Im interested in how your design is working out too.

[mswhin63]

Mine is able to move as well, but it all depends on the new place you move into. I rent so the slab won't fit in the new place :(